Negative research from Green’s playbook against Fernando Ferrer worked so well in 2001, it’s being used again this year – by Republican Mayor Bloomberg.

The day after Ferrer ripped into Hizzoner for giving money to some anti-abortion politicians, the Manhattan Republican Party sent out a familiar e-mail detailing the former Bronx borough president’s conflicting positions on the abortion issue.

“It was valid then. It’s valid now,” said Manhattan GOP Chairman James Ortenzio, who called the Green playbook a “gold mine.”

“I discussed it with the mayor’s people and felt that this was the right timing,” Ortenzio told The Post.

Green defeated Ferrer in a nasty Democratic Party runoff four years ago – only to lose to Bloomberg in the general election.

Bloomberg campaign spokesman Stu Loeser was Green’s research director four years ago.

“This information has gotten around the Internet more than a Paris Hilton video, so it’s no surprise that both Republicans and the Ferrer campaign have it,” Loeser said.

“But what Freddy can’t get around is the indisputable fact that he explicitly wanted to limit a woman’s right to choose, even in the very first months of pregnancy.”

Ferrer said he staunchly supports abortion rights.

Bloomberg picked up the backing this week of the National Abortion Rights Action League and told reporters he won’t support Supreme Court nominee John Roberts unless he clearly supports keeping abortion legal.